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Item Patterns of Mycoplasma bovis antibodies in cows and calves in Swedish dairy herds, and testing strategies to detect seropositive herds(Elsevier Inc on behalf of the American Dairy Science Association®, 2025-10-01) Hurri E; Compton CWR; Alvåsen K; Tråvén MMycoplasma bovis causes severe diseases among cattle. Sweden has a favorable situation for control of this disease, with a low prevalence of M. bovis infected and seropositive herds detected only in the southern parts of the country. To prevent the spread of the infection, analyzing antibody levels is a cost-effective method to determine herd pathogen exposure status. In this study, our aims were to monitor the antibody dynamics in infected herds over time using IDvet ELISA, to both evaluate risk-based sampling and investigate the effect of M. bovis exposure on health and production. We visited and sampled 35 dairy herds, 31 of which were sampled at least 2 times and 26 sampled 4 times and followed for 2 yr. The patterns of herd seroprevalence varied depending on the status before the herd's entry into the study and remained relatively stable at the herd level, although antibody status could differ among age groups. Overall, herds with high exposure prevalence (75%–100% positive cows, n = 13/26), and herds with low exposure prevalence (<25% positive cows, n = 5/26), maintained their exposure status throughout the study. The changes in status observed within the herds, both among calves and cows, included transitions from positive to negative, as well as from negative to positive. In 5 herds, the calf group transitioned from positive to negative, while in 1 herd, the reverse occurred. Three herds exhibited an increase in antibody levels; in 2 of these herds, the cows transitioned from negative to positive, and in 1 herd with positive cows, the calves shifted from negative to positive. A cost-effective test strategy to find likely infected herds involved sampling bulk tank milk and cows with a high SCC, which gave a 90% probability of locating infected herds by the second sampling. Milk production was reduced by 404 kg (1.3 L/d, P = 0.012) in cows positive for M. bovis antibodies. Therefore, controlling the spread of M. bovis infection will likely have a positive effect on reducing income loss for dairy herds in Sweden.Item Do stress, depression and anxiety lead to beliefs in conspiracy theories over time? : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Clinical Psychology at Massey University, Albany, New Zealand(Massey University, 2025-06-28) Fox, NickPrior research has found positive correlations between various indicators of psychological distress such as anxiety, depression and stress, and belief in conspiracy theories. However, whether these relationships reflect causal effects remains unclear. In this preregistered longitudinal study, we tested whether anxiety, depression, and stress affect – and are affected by – belief in unwarranted conspiracy theories. Participants (N = 970) from Australia, New Zealand, and the United Kingdom completed seven monthly online surveys between October 2022 and March 2023. Using a multiple indicator random intercept cross-lagged panel model (RI-CLPM), we found support for only one of 15 preregistered hypotheses: a small within-person cross-lagged effect of anxiety increasing belief in conspiracy theories. Conversely, we found no evidence that belief in conspiracy theories increases psychological distress over time. These findings align with other longitudinal studies, suggesting that any reciprocal relationship between psychological distress and conspiracy beliefs is relatively small. This raises questions about the role of distress and existential threat as primary contributors to belief in conspiracy theories.Item Immune modulating effects of continuous bioaerosol and terpene exposure over three years among sawmill workers in Norway(Nordic Association of Occupational Safety and Health (NOROSH), 2025-09-01) Straumfors A; Haugen F; Skare Ø; Eduard W; Henneberger PK; Douwes J; Ulvestad B; Nordby K-COBJECTIVES: Exposure to wood dust, resin acids, microbial and volatile components among sawmill workers may impair respiratory health, with inflammation indicated as a key mechanism. Previous, mostly cross-sectional studies have shown mixed results, and a conclusive association between wood dust exposure and chronic respiratory inflammation has therefore not yet been established. This study assessed associations between exposure to bioaerosols and volatile terpenes and serum inflammatory marker levels over three years. METHODS: Serum biomarkers and blood cell counts were analyzed based on 702 observations from 450 exposed sawmill workers and 102 observations from 65 unexposed sawmill workers in Norway at baseline and after three years. Job-exposure-matrices, based on measurements among the same cohort, were used to assess exposures for wood dust, endotoxins, resin acid, monoterpenes, fungal spores, and fungal fragments. Changes in exposures, biomarkers and cell counts over the study period, as well as group differences and potential cause-and-effect associations were assessed using linear mixed regression. RESULTS: Exposures were relatively low and below occupational limits, although variances were relatively high (GSDtot 2.1-8.3), largely driven by differences between workers (GSDbw 1.9-7.8). Serum CC-16 and mCRP were slightly higher after three years, whereas IL-1β, TNF-α and IL-10 levels were significantly lower among exposed compared with unexposed workers. Exposures positively associated with increases in biomarker levels included endotoxin with mCRP, monoterpenes with IL-10, and fungal spores with TNF-α and IL-8. Exposed workers had higher counts of total leucocytes, neutrophils, lymphocytes and basophils after three years. Several of the increased leucocyte counts were associated with concurrent increase in mCRP and IL-6 concentrations, predominantly in the exposed group. Conversely, increased CC-16 levels were associated with lower leucocyte and neutrophil counts, mainly in the unexposed group. CONCLUSION: Continuous exposure to wood dust and related components for three years appears to induce a chronic low-grade inflammatory response among sawmill workers with a shift in cytokine profiles towards a less regulated, potentially more muted immune state.Item Social connections and risk of incident mild cognitive impairment, dementia, and mortality in 13 longitudinal cohort studies of ageing.(Wiley Periodicals LLC on behalf of Alzheimer’s Association., 2023-11) Mahalingam G; Samtani S; Lam BCP; Lipnicki DM; Lima-Costa MF; Blay SL; Castro-Costa E; Shifu X; Guerchet M; Preux P-M; Gbessemehlan A; Skoog I; Najar J; Sterner TR; Scarmeas N; Yannakoulia M; Dardiotis T; Kim K-W; Riedel-Heller S; Röhr S; Pabst A; Shahar S; Numbers K; Ganguli M; Hughes TF; Chang C-CH; Crowe M; Ng TP; Gwee X; Chua DQL; Rymaszewska J; Wolf-Ostermann K; Welmer A-K; Stafford J; Mélis R; Vernooij-Dassen M; Jeon Y-H; Sachdev PS; Brodaty H; SHARED consortium for the Cohort Studies of Memory in an International Consortium (COSMIC)INTRODUCTION: Previous meta-analyses have linked social connections and mild cognitive impairment, dementia, and mortality. However, these used aggregate data from North America and Europe and examined a limited number of social connection markers. METHODS: We used individual participant data (N = 39271, Mage = 70.67 (40-102), 58.86% female, Meducation = 8.43 years, Mfollow-up = 3.22 years) from 13 longitudinal ageing studies. A two-stage meta-analysis of Cox regression models examined the association between social connection markers with our primary outcomes. RESULTS: We found associations between good social connections structure and quality and lower risk of incident mild cognitive impairment (MCI); between social structure and function and lower risk of incident dementia and mortality. Only in Asian cohorts, being married/in a relationship was associated with reduced risk of dementia, and having a confidante was associated with reduced risk of dementia and mortality. DISCUSSION: Different aspects of social connections - structure, function, and quality - are associated with benefits for healthy aging internationally. HIGHLIGHTS: Social connection structure (being married/in a relationship, weekly community group engagement, weekly family/friend interactions) and quality (never lonely) were associated with lower risk of incident MCI. Social connection structure (monthly/weekly friend/family interactions) and function (having a confidante) were associated with lower risk of incident dementia. Social connection structure (living with others, yearly/monthly/weekly community group engagement) and function (having a confidante) were associated with lower risk of mortality. Evidence from 13 longitudinal cohort studies of ageing indicates that social connections are important targets for reducing risk of incident MCI, incident dementia, and mortality. Only in Asian cohorts, being married/in a relationship was associated with reduced risk of dementia, and having a confidante was associated with reduced risk of dementia and mortality. Highlights Social connection structure (being married/in a relationship, weekly community group engagement, weekly family/friend interactions) and quality (never lonely) were associated with lower risk of incident MCI. Social connection structure (monthly/weekly friend/family interactions) and function (having a confidante) were associated with lower risk of incident dementia. Social connection structure (living with others, yearly/monthly/weekly community group engagement) and function (having a confidante) were associated with lower risk of mortality. Evidence from 13 longitudinal cohort studies of ageing indicates that social connections are important targets for reducing risk of incident MCI, incident dementia, and mortality. Only in Asian cohorts, being married/in a relationship was associated with reduced risk of dementia, and having a confidante was associated with reduced risk of dementia and mortality.Item TeamMate: A Longitudinal Study of New Zealand Working Farm Dogs. III. Factors Affecting the Risk of Dogs Being Lost from the Workforce(MDPI (Basel, Switzerland), 2021-06) Isaksen KE; Linney L; Williamson H; Norman EJ; Cave NJ; Cogger NWorking farm dogs are essential to many livestock farmers. Little is known about factors that influence dogs’ risk of being lost from work. This paper explores risk factors for farm dogs being lost through death, euthanasia and retirement. All enrolled dogs were working and a minimum of 18 months old. Five data collection rounds were performed over four years. Data about dogs were collected from owners and dogs were given physical examinations by veterinarians. Dogs that were lost from work were counted and owner-reported reasons for loss were recorded. Multivariable logistic regression modelling was used to investigate risk factors for loss. Of 589 dogs, 81 were lost from work. Of these, 59 dogs died or were euthanized and 22 were retired. Farm dogs tended to reach advanced ages, with 38% being 10 years or older when last examined. Acute injury or illness was the most commonly owner-reported reason for loss. Age group (p < 0.0001) and lameness (p = 0.04, OR = 1.8) significantly affected dogs’ risk of being lost. These results expand our knowledge about factors that affect health, welfare and work in farm dogs. Further investigation into reasons for lameness may help improve health and welfare in working farm dogs.Item Depression and loneliness as mediators of purpose in life and quality of life in older adults : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Psychology at Massey University, Distance, New Zealand(Massey University, 2023) Williams, AleishaObjective: Worldwide populations are aging. This can potentially be a valuable resource to both the older individual and their communities or an ethical burden. A key factor in determining the potential opportunities that arise from these extra years of life is well being. It is therefore important to understand determinants that foster healthy aging and well being through maximising functional ability and enabling engagement in things that matter to them. This study utilises Quality of Life as a holistic measure of a well-being in older age. The existing literature has provided some support for Purpose in Life, Loneliness, and Depression as being associated with each other; it also suggests they are important pre determinants of older adult Quality of Life. Based on previous literature it is possible the relationship between Purpose in Life and Quality of Life is partially mediated by Loneliness and Depression. Method: A structural equation model tested the longitudinal relationship between Purpose in Life and Quality of Life, and the potential parallel mediating effect of Loneliness and Depression, while controlling for Age, Gender, Marital Status, Social Support, Social Isolation and Socioeconomic Status. Sample: The analysis used observational survey-based secondary data obtained from three waves of the New Zealand Health, Work and Retirement Study. The participants represented older adults living in New Zealand, aged 55 years and over. Results: Correlational analysis found significant correlational relationships between the latent variables. Regression analysis found positive direct (B = .243) and indirect total effect (B = .227) relationships between Purpose in Life and Quality of Life. However, indirect effects were not significant when one mediator was controlled for. Conclusion: The current research supports prior findings that Purpose in Life predicts future Quality of Life in older adults and offers an important contribution towards future interventions aimed at older adult well-being. The mixed mediating results suggest further research is needed to understand the role of Loneliness and Depression as potential pathways between Purpose in Life and Quality of Life.Item Longitudinal assessments highlight long-term behavioural recovery in disorders of consciousness(Oxford University Press on behalf of the Guarantors of Brain, 2019) Bareham CA; Allanson J; Roberts N; Hutchinson PJA; Pickard JD; Menon DK; Chennu SAccurate diagnosis and prognosis of disorders of consciousness is complicated by the variability amongst patients’ trajectories. However, the majority of research and scientific knowledge in this field is based on cross-sectional studies. The translational gap in applying this knowledge to inform clinical management can only be bridged by research that systematically examines follow-up. In this study, we present findings from a novel longitudinal study of the long-term recovery trajectory of 39 patients, repeatedly assessed using the Coma Recovery Scale-Revised once every 3 months for 2 years, generating 185 assessments. Despite the expected inter-patient variability, there was a statistically significant improvement in behaviour over time. Further, improvements began approximately 22 months after injury. Individual variation in the trajectory of recovery was influenced by initial diagnosis. Patients with an initial diagnosis of unresponsive wakefulness state, who progressed to the minimally conscious state, did so at a median of 485 days following onset—later than 12-month period after which current guidelines propose permanence. Although current guidelines are based on the expectation that patients with traumatic brain injury show potential for recovery over longer periods than those with non-traumatic injury, we did not observe any differences between trajectories in these two subgroups. However, age was a significant predictor, with younger patients showing more promising recovery. Also, progressive increases in arousal contributed exponentially to improvements in behavioural awareness, especially in minimally conscious patients. These findings highlight the importance of indexing arousal when measuring awareness, and the potential for interventions to regulate arousal to aid long-term behavioural recovery in disorders of consciousness.Item Ischaemic Heart Disease and Occupational Exposures: A Longitudinal Linkage Study in the General and Māori Populations of New Zealand(Oxford University Press on behalf of the British Occupational Hygiene Society, 2022-05) Barnes LA; Eng A; Corbin M; Denison HJ; 't Mannetje A; Haslett S; McLean D; Ellison-Loschmann L; Jackson R; Douwes JOBJECTIVES: This study assessed associations between occupational exposures and ischaemic heart disease (IHD) for males and females in the general and Māori populations (indigenous people of New Zealand). METHODS: Two surveys of the general adult [New Zealand Workforce Survey (NZWS); 2004-2006; n = 3003] and Māori population (Māori NZWS; 2009-2010; n = 2107), with information on occupational exposures, were linked with administrative health data and followed-up until December 2018. Cox proportional hazards regression (adjusted for age, deprivation, and smoking) was used to assess associations between organizational factors, stress, and dust, chemical and physical exposures, and IHD. RESULTS: Dust [hazard ratio (HR) 1.6, 95%CI 1.1-2.4], smoke or fumes (HR 1.5, 1.0-2.3), and oils and solvents (HR 1.5, 1.0-2.3) were associated with IHD in NZWS males. A high frequency of awkward or tiring hand positions was associated with IHD in both males and females of the NZWS (HRs 1.8, 1.1-2.8 and 2.4, 1.1-5.0, respectively). Repetitive tasks and working at very high speed were associated with IHD among NZWS females (HRs 3.4, 1.1-10.4 and 2.6, 1.2-5.5, respectively). Māori NZWS females working with vibrating tools and those exposed to a high frequency of loud noise were more likely to experience IHD (HRs 2.3, 1.1-4.8 and 2.1, 1.0-4.4, respectively). Exposure to multiple dust and chemical factors was associated with IHD in the NZWS males, as was exposure to multiple physical factors in males and females of the NZWS. CONCLUSIONS: Exposures associated with an elevated IHD risk included dust, smoke or fumes, oils and solvents, awkward grip or hand movements, carrying out repetitive tasks, working at very high speed, loud noise, and working with tools that vibrate. Results were not consistently observed for males and females and between the general and Māori populations.